Have you ever wanted a smart LED display that could easily be lost in your pocket? The 490IP1 LED, produced in the former Soviet Union, is a likely contender for the smallest smart LED display in the world. This display has a built in decimal counter and 7 segment encoder etched into a single die, which can be easily seen through the LED's glass front. This display is insanely small; the digit height is only 2.5mm and this device is a tiny fraction of the size of electrically comparable decimal counter LEDs such as the Texas Instruments TIL306. The 490IP1 has a maximum counting speed of 1MHz as well as a carry output that allows multiple LEDs to be chained together. In effect, this LED can be thought of as a functional replacement for the Elesta EZ10B dekatron counting tube, though since the 490IP1 is not filled with chronically leaky hydrogen gas, it is likely a much more robust device.

Since the display area of the 490IP1 is very small, the Soviets produced a companion external magnifier designed to work with this LED. The magnifier would clip to the outside of the display and provide a bubble lens over the digit area, to make the display easier to read.

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Soviet 490IP1 LED display, normal operation. The 490IP1 is likely one of the smallest smart LED displays ever produced.

This display uses a unusual glass and ceramic package with leads arranged in a very tight DIP configuration.

The built in logic die contains a decimal counter as well as a 7 segment decoder to drive the LEDs.